Tony Stark has made more than his fair share of enemies within the Marvel Universe, both as the CEO of Stark Industries and as the superhero Iron Man, who all want to topple the empire and the heroic legacy that Tony has built for himself. But while many of Tony's fellow Avengers have their own clearly identifiable archenemy -- from Captain America and the Red Skull to Thor and Loki -- the Armored Avenger doesn't quite have a nemesis that can be firmly established as his biggest foe.

Now, CBR is taking a look at some of the most menacing candidates for Iron Man's greatest villain and their respective antagonistic legacies.

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Obadiah Stane

iron-monger

Created by Denny O'Neil and Luke McDonnell in 1982's Iron Man #163, Obadiah Stane was first introduced as a business rival of Tony's, leading the arms manufacturer Stane International while seeking to usurp Tony as the head of Stark International. While covering his tracks, Stane orchestrates attacks across Tony's professional and personal life, including severely injuring James Rhodes, before the mounting toll causing Tony to relapse into alcoholism and forced him to sell his company to Stane. Eventually recovering, Tony confronts Stane in his new Silver Centurion armor only to discover Stane had created his own armor as the Iron Monger. After being defeated, Stane opts to commit suicide rather than face arrest and conviction for his crimes.

Obadiah's villainous legacy would live on through his son Ezekiel, created by Matt Fraction and Barry Kitson in 2008's The Order #8. Zeke would attempt to avenge his father's death by systemically targeting Stark Industries through his own alliances and pirated Stark tech before Tony similarly defeated the young Stane to stop the family's vendetta against him. Jeff Bridges would later portray Obadiah in the first Iron Man film as the Marvel Cinematic Universe's first primary antagonist before meeting his ultimately end in the climax.

Justin Hammer

Justin Hammer in the MCU

Created by David Michelinie, Bob Layton, and John Romita, Jr. in 1979's Iron Man #120, Justin Hammer was created as arms manufacturer and war profiteer as a sinister analogue of what Tony could have become had he not decided to become a superhero. Secretly funding criminal activities and upgrades to help forward his own agenda, Hammer framed Tony for murder by temporarily taking control of the Iron Man armor. After acquiring Stane International following the death of Obadiah Stane, Hammer had Spymaster steal Stark tech to upgrade several of Iron Man's enemies significantly and face the Armored Avenger.

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Using Stane International as a front, Hammer orchestrated attacks on Stark through his alliances with HYDRA and Roxxon. While continuing to finance criminals to assault Tony and his assets, Hammer eventually discovered he had developed terminal cancer and injected Tony with nanites to make his old foe's behavior more erratic. However, before he could enact his final plan to destroy Tony, Hammer accidentally froze to death  while confronting him on a space station and ejected himself into outer space. While Justin Hammer's daughter Justine and granddaughter Sasha would continue the feud, none have had the calculated cunning of their predecessor. Justin would be portrayed by Sam Rockwell in Iron Man 2 as one of the film's main antagonists.

The Mandarin

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Created by Stan Lee and Don Heck in 1964's Tales of Suspense #50, the Mandarin was a man who discovered the wreckage of an alien spaceship within a remote valley in his native China. Learning how to master the advanced technology and channel it through ten rings found in the crash, the Mandarin becomes to create his own empire within China, and begins using repurposed Stark tech to attack other countries, causing an inevitable collision course against Iron Man.

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The figures would become recurring foes over the years, both as their super-powered personas and within the corporate world, especially as Stark Industries expanded its presence into China and Hong Kong. The two characters have strong paralleled origins as well: Both Tony and the Mandarin had entered a cave and emerged reborn with advanced technology but while Tony had used his for redemptive good, the Mandarin had used his for domineering conquest.

While he isn't always a factor in Iron Man's world, the Mandarin always poses a serious threat to Stark whenever he shows up. In the Iron Man cartoons of both the '60s and the '90s, the Mandarin was the Avenger's main villain, and that reputation has never quite faded away. As the most recurring and powerful foe in Iron Man's extensive roster of villains, the Mandarin is the clear, true archenemy of Tony Stark.